/* copyright (c) 2022 - 2025 grunfink et al. / MIT license */ #ifndef _XS_URL_H #define _XS_URL_H xs_str *xs_url_dec(const char *str); xs_str *xs_url_enc(const char *str); xs_dict *xs_url_vars(const char *str); xs_dict *xs_multipart_form_data(const char *payload, int p_size, const char *header); #ifdef XS_IMPLEMENTATION char *xs_url_dec_in(char *str, int qs) { char *w = str; char *r; for (r = str; *r != '\0'; r++) { switch (*r) { case '%': { unsigned hex; if (!r[1] || !r[2]) return NULL; if (sscanf(r + 1, "%2x", &hex) != 1) return NULL; *w++ = hex; r += 2; break; } case '+': if (qs) { *w++ = ' '; break; } /* fall-through */ default: *w++ = *r; } } *w++ = '\0'; return str; } xs_str *xs_url_dec(const char *str) /* decodes an URL */ { xs_str *s = xs_str_new(NULL); while (*str) { if (!xs_is_string(str)) break; if (*str == '%') { unsigned int i; if (sscanf(str + 1, "%02x", &i) == 1) { unsigned char uc = i; if (!xs_is_string((char *)&uc)) break; s = xs_append_m(s, (char *)&uc, 1); str += 2; } } else if (*str == '+') s = xs_append_m(s, " ", 1); else s = xs_append_m(s, str, 1); str++; } return s; } xs_str *xs_url_enc(const char *str) /* URL-encodes a string (RFC 3986) */ { xs_str *s = xs_str_new(NULL); while (*str) { if (isalnum(*str) || strchr("-._~", *str)) { s = xs_append_m(s, str, 1); } else { char tmp[8]; snprintf(tmp, sizeof(tmp), "%%%02X", (unsigned char)*str); s = xs_append_m(s, tmp, 3); } str++; } return s; } xs_dict *xs_url_vars(const char *str) /* parse url variables */ { xs_dict *vars; vars = xs_dict_new(); if (xs_is_string(str)) { xs *dup = xs_dup(str); char *k; char *saveptr; for (k = strtok_r(dup, "&", &saveptr); k; k = strtok_r(NULL, "&", &saveptr)) { char *v = strchr(k, '='); if (!v) continue; *v++ = '\0'; k = xs_url_dec_in(k, 1); v = xs_url_dec_in(v, 1); if (!xs_is_string(k) || !xs_is_string(v)) continue; const char *pv = xs_dict_get(vars, k); if (!xs_is_null(pv)) { /* there is a previous value: convert to a list and append */ xs *vlist = NULL; if (xs_type(pv) == XSTYPE_LIST) vlist = xs_dup(pv); else { vlist = xs_list_new(); vlist = xs_list_append(vlist, pv); } vlist = xs_list_append(vlist, v); vars = xs_dict_set(vars, k, vlist); } else { /* ends with []? force to always be a list */ if (xs_endswith(k, "[]")) { xs *vlist = xs_list_new(); vlist = xs_list_append(vlist, v); vars = xs_dict_append(vars, k, vlist); } else vars = xs_dict_append(vars, k, v); } } } return vars; } xs_dict *xs_multipart_form_data(const char *payload, int p_size, const char *header) /* parses a multipart/form-data payload */ { xs *boundary = NULL; int offset = 0; int bsz; char *p; /* build the boundary string */ { xs *l1 = xs_split(header, "="); if (xs_list_len(l1) != 2) return NULL; xs *t_boundary = xs_dup(xs_list_get(l1, 1)); /* Tokodon sends the boundary header with double quotes surrounded */ if (xs_between("\"", t_boundary, "\"") != 0) t_boundary = xs_strip_chars_i(t_boundary, "\""); boundary = xs_fmt("--%s", t_boundary); } bsz = strlen(boundary); xs_dict *p_vars = xs_dict_new(); /* iterate searching the boundaries */ while ((p = xs_memmem(payload + offset, p_size - offset, boundary, bsz)) != NULL) { xs *vn = NULL; xs *fn = NULL; xs *ct = NULL; char *q; int po, ps; /* final boundary? */ p += bsz; if ((p - payload) + 2 > p_size || (p[0] == '-' && p[1] == '-')) break; /* skip the \r\n */ p += 2; /* Tokodon sends also a Content-Type headers, let's use it to determine the file type */ do { xs *s1 = NULL; xs *l1 = NULL; if (p[0] == '\r' && p[1] == '\n') break; q = memchr(p, '\r', p_size - (p - payload)); /* unexpected formatting, fail immediately */ if (q == NULL) return p_vars; s1 = xs_realloc(NULL, q - p + 1); memcpy(s1, p, q - p); s1[q - p] = '\0'; if (xs_startswith(s1, "Content-Disposition") || xs_startswith(s1, "content-disposition")) { /* split by " like a primitive man */ l1 = xs_split(s1, "\""); /* get the variable name */ vn = xs_dup(xs_list_get(l1, 1)); /* is it an attached file? */ if (xs_list_len(l1) >= 4 && strcmp(xs_list_get(l1, 2), "; filename=") == 0) { /* get the file name */ fn = xs_dup(xs_list_get(l1, 3)); } } else if (xs_startswith(s1, "Content-Type") || xs_startswith(s1, "content-type")) { l1 = xs_split(s1, ":"); if (xs_list_len(l1) >= 2) { ct = xs_lstrip_chars_i(xs_dup(xs_list_get(l1, 1)), " "); } } p += (q - p); p += 2; // Skip /r/n } while (1); /* find the start of the part content */ if ((p = xs_memmem(p, p_size - (p - payload), "\r\n", 2)) == NULL) break; p += 2; // Skip empty line /* find the next boundary */ if ((q = xs_memmem(p, p_size - (p - payload), boundary, bsz)) == NULL) break; po = p - payload; ps = q - p - 2; /* - 2 because the final \r\n */ /* is it a filename? */ if (fn != NULL) { /* p_var value is a list */ /* if filename has no extension and content-type is image, attach extension to the filename */ if (strchr(fn, '.') == NULL && ct && xs_startswith(ct, "image/")) { char *ext = strchr(ct, '/'); ext++; fn = xs_str_cat(xs_str_new(""), fn, ".", ext); } xs *l1 = xs_list_new(); xs *vpo = xs_number_new(po); xs *vps = xs_number_new(ps); l1 = xs_list_append(l1, fn); l1 = xs_list_append(l1, vpo); l1 = xs_list_append(l1, vps); if (xs_is_string(vn)) p_vars = xs_dict_append(p_vars, vn, l1); } else { /* regular variable; just copy */ xs *vc = xs_realloc(NULL, ps + 1); memcpy(vc, payload + po, ps); vc[ps] = '\0'; if (xs_is_string(vn) && xs_is_string(vc)) p_vars = xs_dict_append(p_vars, vn, vc); } /* move on */ offset = q - payload; } return p_vars; } #endif /* XS_IMPLEMENTATION */ #endif /* XS_URL_H */